Smart connected devices are growing at an unprecedented rate and are expected to hit 2.4 billion units per year by 2018. According to new research, that growth will be driven by smart phones and cheaper (sub-$500) gadgets, which will begin to push traditional PCs into the margins.

According to IDC's latest Worldwide Quarterly Smart Connected Devices Tracker, smart phones will outpace traditional PCs by a 6-to-1 margin by 2018. Desktops, which currently make up 8.89 percent of overall smart connected devices (as of year-end 2013), will drop to 4.9 percent in 2018. Laptops and other portable PCs will fall from 11.59 percent to 6.9 percent.

"Apple's iOS-ification of Mac OS, and Microsoft's implementation of Modern UI throughout different form factors are clear indicators that we're living in a mobile-first world," said Jitesh Ubrani, research analyst, Worldwide Quarterly Tablet Tracker, in a prepared statement. "The PC will be the new accessory to mobile as smartphones become the first and primary computing device for many."

Tablets and combo devices will remain essentially flat, shifting from 14.19 percent of the market in 2013 to 14.1 percent in 2018.

That shift will also mean changes for average price points in the smart connected devices market. At present (end of year 2013), the share of devices at $200 or less is 32.7 percent; devices at $200 to $499 are 34.3 percent and devices priced at $500 or more make up 33 percent of the market. That high end will drop to 29.2 percent this year, while the low jumps to 37.2 percent. And by 2018, the high end will plummet to a 21.1 percent share of the market, while the low end continues its climb, reaching 43.3 percent. (The mid-range will change little in the forecast period.)

"Low-cost Android smartphones will drive much of the SCD shipment growth in coming years," said Tom Mainelli, program vice president for IDC's Devices and Displays group. "The influx of inexpensive phones will drive the SCD average selling price bands downward, with the sub-$200 band increasing from 33% of total shipments in 2013 to greater than 43% in 2018, while devices that cost more than $500 are forecast to shrink from 33% of total device shipments to 21.1%."

Executive Producer David Nagel heads up the editorial department for 1105 Media's education publications — which include two daily sites, a variety of newsletters and two monthly digital magazines covering technology in both K-12 and higher education.

A 21-year publishing veteran, Nagel has led or contributed to dozens of technology, art and business publications.